Explosion or internal combustion engine



Dec. 14, 19.37. I M. KADENACY EXPLOSION OR INTERNAL COMBUSTION ENGINE Filed Aug. 1, 1934 Patented Dec. 14, 1937 ENGINE Michel Kadenacy, Paris, France Application August 1, 1934, Serial No. 738,014

. In France August 1, 1933 9 Claims.

having the properties similar to those of a resilient body and behaving as though it possessed a high initial velocity while still in the cylinder. The applicant has stated that if this body is allowed to do so it will leave the cylinder through the exhaust orifice as a mass, which in itself is the consequence of its high initial velocity, and it will evacuate the cylinder completely or substantially completely. Subsequently, as a consequence of its impact upon the external gaseous medium and of the fact that the velocity of the said mass is greater than the possible velocity of compression of the external gaseous medium, the reac-' tion from the latter will cause the said mass of burnt gases to rebound into the cylinder, and all the above mentioned phenomena occur when no exhaust system is provided incontinuation of the exhaust orifice.

The present invention relates to such engines, that is to say to engines wherein the burnt gases are evacuated from the cylinder through the exhaust orifice as a mass or body.

In the applicants above mentioned prior specifications he has proposed, in such an engine, to utilize the evacuation of the cylinder for the purpose of recharging the cylinder, but at the time when such specifications were filed, his researches had led him to believe that it was essential in the operation of such engines to close the exhaust orifice in such a manner that the resulting vacuous condition in the cylinder remained available for securing the entry of the subsequent charge.

The applicant has now been led by his further consideration of the phenomena in questionto devise a method of charging such engines which is independent in principle of the closure of the exhaust orifice and which avoids all the practical objections that arise when use is made of the means described in the above mentioned prior British specifications.

This method consists in arranging for the inlet orifice to open, at the normal speed of the engine,

after the exhaust orifice opens but only with the required delay to ensure that the burnt gases are then moving outwardly through the exhaust orifice or duct as a consequence of their mass exit from the cylinder, and cause a suction effect to be exerted in the cylinder at the said inlet orifice.

If the inlet is opened in the manner specified, air or a carburetted mixture of air and fuel according to the type of engine under consideration is suddenly drawn into the cylinder and the latter is filled satisfactorily so much the more as the gases thus admitted at a high speed are, on account of their inertia, compressed to a pressure greater than that existing in the inlet duct; and this timing of inlet establishes the engine as a ,two-stroke cycle engine.

- The return of the tail end of the column of exhaust gases tends to occur after the cylinder has been filled with fresh gases, but the re-entry of this tail end of the exhaust column into the cylinder is resisted by the charge of fresh gases contained therein, so that the following cycle normally takes place under the most satisfactory conditions.

Now the intervals elapsing between the opening of the exhaust orifice, the mass exit of the burnt gases, and the return of this mass to the cylinder are intervals of time which are substantially independent of engine speed and consequently they extend over larger crank angles at high engine speeds than at low engine speeds.

It therefore follows that for an engine in which the valve gear, on the one hand, and the exhaust device, on the other hand, have fixed characteristics, there is also for this engine a definite working speed having a lower limit and an upper limit relatively close to each other, from which this working speed cannot depart without the engine ceasing to operate in the desired manner.

According to the invention means are provided whereby the engine is enabled to operate in the desired manner between wider working limits, a will be hereinafter described.

The invention further provides means for allowing this engine to start and to reach a working speed for which the above phenomena can occur.

These means consist either in a valve or other suitably arranged equivalent device, or again in a device for the injection, into the cylinder, of air under a relatively low pressure, upon starting. This injection of air is adapted to prevent the return of the exhaust gases into the cylinder, and to thus allow the operation until-the engine has acquired suflicient speed.

Various forms of carrying out the subject-matter of the invention will be described hereinafter,

with reference to the accompanying diagrammatic drawing, in which:

Figure 1 is a longitudinal section through an engine cylinder provided with an exhaust pipe.

by a push-rod 6a and rocker arm 6. The pushrod to. is actuated'by a cam 61) on the usual cam shaft, being geared by means of timing gears g-g (illustrated in the present embodiment as of 1-1 ratio) to the crank shaft 3b. The conduit 4 serves for the admission of the carburetted mixture ii. an explosionengipe is under consideration, or of air if an internal combustion engine is considered and, in the "latter case, the cylinder would also carry an injector for the admission of the iuel at the end of the compression. "--.-The present embodiment illustrates an explosion engine having a suitable ignition element, e. g., the spark plug S.

The exhaust takes place through a conduit 1 opening in the cylinder by means of a port 8 uncovered by the piston, when the latter comes in proximity to its lower dead centre, and, according to the invention, the characteristics of the distribution and exhaust devices are such that the inlet is openedat the time the gaseous column is formed, according to the method described, in the conduit 1 and in the device followin it, this column escaping at a high speed tow ds the exterior. l v

According'to a particular arrangement of the invention, the exhaust device is adjustable in such a manner that thchronological law of the phenomena-taking place therein can be varied 'at will, and that it is thus possible, as previously explained, to widen the limits between which the working'speed of the engine can vary.

By way of example, the figures of the accompanying'drawing illustrate devices comprising an exhaust conduit the useful length of which can be varied.

The body of gases in this conduit is subjected to corresponding variations and, consequently,

it is more or less rapidly shaken by the body of gases issuing from the cylinder at the end of the! eiTpansion a nd which strikes against it and reed, and, consequently, this new arrangement corresponds to a lower speed of the engine.

ure 1, the exhaust conduit comprises the'fixed':

. I tube 1 previously mentioned, and, at the end of this fixed tube, a sliding tube 9.

The position illustrated in full lines corresponding to a definite working speed, in order to be able toreduce this speed, the tube 9 is moved in the direction indicated by the arrow F,

up to a position such as that shown in dot and dash lines. The increase 11 of the useful length of the exhaust conduit involves an increase of the body of gases contained in this conduit, and, consequently, causes the setting in motion of the gases, in the form of a column having a rapid movement, to be retarded.

Another particular arrangement of the invention, adapted to appreciably promote the phenomena above described, consists in that the exhaust device is arranged for facilitating the movement of the gases in the direction for exhaust, and, on the contrary, for checking it in the reverse direction.

In the example illustrated in Figure 1, and in detail and on an enlarged scale in Figure 2, the tube I is,in the shape of a frustum having an inclination i and outwardly flared, this inclination i being of the order 1 to 2 per cent, for instance.

The increase of the section of the passageway for the gases in proportion asthey escape, facilitates this movement, but. reversely, if the tail end of the gas column expands backwardly, this section decreases and hinders said expansion; this concurs to prevent the return of the gases into the cylinder and, consequently, to further improve the operation.

In the form of construction shown in Figure 3, the fixed tube 1 extends in the exhaust box l0, and its end is covered within this exhaust box by a sliding tube II, the bottom Ha of which is closed, so that the gas column escapes according to the path indicated by the arrows F1. The bot tom I la of the sliding tube 1 I, and the portion l-Oa of the wall of the exhaust box In throu h which passes the tube 1, constitute deflectors facilitating the changes in the direction of themovement of the gases.

The structure is so arranged that the gas column escaping ,at high speed in the direction F, enters the eyiaust boxafter it has produced its entire usefu effect, that is, when it has reached substantial the cylin r.

By such the limit of its outward travel from as that shown in dot and dash lines, the

mo ving the sliding tube u to a positibn .J/Qi me of gase contained in the exh'aust tube is increased according to a quantity-V, and this new arrangement corresponds to a lower speed of the engine.

' Finally, according to an arrangement similar] to that described, the tube 1 and the tubular portion 10b of the exhaust box H! which surrounds the tubes I and II have outwardly flared shapes. I e

Acfiirding to the form 01' construction illustrated in Figure 4, the tubular portion ll oi'the preceding device is replaced by another tube l2,"

having also a closed bottom l2a,-and rigid with" a guide [3 sliding on the tube 1, and, moreover, another tube H slides on the-tube 1 ans on the end of the tube l2, so that by'mov-ing both these ..tubes .l,2, l.l, simultaneously or separately, a greater range of adjustment is available, and this adjustment can be effected more accurately.

It is to be understood that, in order to actuate the adjusting means. described, or any other e equivalent means, any

suitable'control can be provided l Finally, for allowing the starting andspeeding up ofthe engine, that is to say, its operation at abnormal working speeds, for which thephenomena described 'no longer take place in the same conditions, and would no longer-ensure satisfactory working of the engine, the invention provides the use of any suitable device arranged for blowing air into the cylinder and thus preventing the return of the exhaust gases. The air pressure necessary is moreover very small, and the device to be used can be of the most simple type.

For example, as shown in Figure 1 the inlet duct 4 may communicate through a two-way rotary valve l8, having a handle IS, with a duct open to the atmosphere and a duct I! opening into the crank case IS, the cylinder comprising a third port ii for the admission of air into the crankcase in the well known manner.

I claim:

1. Method of controlling two-stroke cycle. internal combustion engines, which comprises establishing communication between thecyllnder and exhaust system during the firing stroke,

maintaining permanent open communication be tween the cylinder and the atmosphere while the exhaust port isopen, providing for the issuance of the burnt gases from the cylinder-substantially as a mass in an interval of time shorter than that which would be required for the burntgases to expand down to the ambient pressure by 'adiabatic flow, whereby the mass oflgases moves outinterval elapsing between the said exit of the burnt gases and the instant when the pressure of the returning gases becomes effective within the I cylinder, whereby there-entry of the said burnt gases into the cylinder will be opposed by the I fresh charge'contained therein.

'2. Method of controlling two-stroke cycle in.- it'brnal'combustion engines, which comprises establishing communication ,between the cylinder of tim' shorter than that which would be re- 55 and exhaust system during the firing stroke, pror theissuance of the burnt gases from 'rsubstantially as a mass in an interval quired for 'the burnt gases to expand down to the ambient pressure by adiabatic flow, whereby the mass of gases moves outward and thereafter returns from a point which may be within the exof said burnt gases, preventing the entrance of fresh charging aii until the said issuance of the causes a suction effect to be exerted in the cyl- ,suance of the burnt gases is in full progress and inder, while the exhaust port is still open, and providing for the said fresh charge to occupy the cylinder in the interval elapsing between the said exit of the burnt gases and the instant when the pressure of the returning gases becomes effective within the cylinder, whereby the re-entry of the said burnt gases into the cylinder will be opposed by the fresh charge contained therein.

' 3. Method of controlling two-stroke cycle internal combustion engines, which comprises establishing communication between the cylinder and exhaust system during the firing stroke, admitting fresh charging air into the cylinder under pressure when starting and running up to normal speeds, providing at normal running speed for the issuance of the burnt gases from the cylinder substantially as a mass in an interval of time shorter than that which would be required for the burnt gases to expand down to the ambient pressure by adiabatic flow, whereby the mass of gases moves outward and thereafter returns from a point which may be within the exhaust system, providing a permanent free passage for the burnt gases to the limit of outward travel of said gases, preventing at normal running speed the entrance of fresh charging air until the said issuanceof the burnt gases is in full progress, admitting at normal running speed fresh charging air into the cylinder, when the said issuance of the burnt gases is in full progress and causes a suction effect to be exerted in the cylinder, while the exhaust port is still open, and providing for the said fresh charge to occupy the cylinder in the interval elapsing between the said exit of the burnt gases and the instant when the pressure of the returning gases becomes effective within the cylinder, whereby, the re-entry of the said burnt gases into the cylinder will be opposed by the fresh charge contained therein.

4. A two-stroke, cycle internal combustion engine having a cylinder, a piston moving in the cylinder, exhaust and inlet orifices in the cylin-, der, an exhaust conduit on the exhaust orifice,

means for so controlling the exhaust orifice dur ing the firing stroke as to ensure, the issuance of the burnt gases as a mass, whereby the said mass moves outward and thereafter returns from a point which may be within the said conduit, means for so controlling the inlet orifice as to ensure that it will be opened while the exhaust orifice is still open and when the said issuanceof the burnt gases is in full progress and pro-9 duces a suction effect in the cylinder, the exhaust the burnt gases to the limit of outward travel of said gases, and providing a passage for the gases during their outward motion as a mass having no cross section of substantially greater area than any cross section thereof further from the cylinder.

5. A two-stroke cycle internal combustion ene ginehaving a cylinder, a piston moving in the cylinder, exhaust and inlet orifices in the cylinder, an exhaust duct on the exhaust orifice means for so controlling the exhaust orifice during the'filitlg stroke as to ensure the issuance.

of the burnt gases as a mass, whereby the said mass moves outward and thereafter returns from a point which may be within the said conduit, means for so controlling the inlet orifice as to ensure that it will be opened while the "exhaust orifice is still open and when the said issuance of theburnt gases is in full progress and produces a suction effect in the cylinder, an exhaust conduit in continuation of the said exhaust orifice, the said conduit providing a permanent free passage for the burn gases to the limit of outward travel of said gases and providing a passage for 6. A two-stroke cycle internal combustion engine as claimed in claim 5, the said passage proconduit providing a permanent free passage-for the gases during their outward motion having,

vided by the exhaust conduit having a taper of the order of 1 to 2 per cent.

7. A two-stroke cycle internal combustion engine having a cylinder, a piston moving in the cylinder, exhaust and inlet orifices in the cylinder, an exhaust conduit on the exhaust orifice, means for so controlling the exhaust orifice during the firing stroke as to ensure the issuance of the burnt gases as a mass, whereby the said mass moves outward and thereafter returns from a point which may be within the said conduit, means for so controlling the inlet orifice as to ensure that it will be opened while the exhaust orifice is still open and when the said issuance of the burnt gases is in full progress and produces a suction effect in the cylinder, the said conduit providing a permanent free passage for the burnt gases to the limit of outward movement of said gases and providing a passage for the gases during their outward motion as a mass having no cross section of substantially greater 8. A two-stroke cycle internal combustion engine having a cylinder, a piston moving in the cylinder, exhaust and inlet orifices in the cylinder, an exhaust conduit on the exhaust orifice, means for so controlling the exhaust orifice during the firing stroke as to ensure the issuance of the burnt gases as a mass, means for so controlling the inlet orifice as to ensure that it will be opened While the exhaust orifice is still open and when the said issuance of the burnt gases is in full progress and produces a suction effect in the cylinder, the said conduit providing a permanent free passage for the burnt gases to the limit of outward travel of said gases and providing a passage for the gases during their outward motion as a mass having no cross section of substantially greater area than any cross section thereof .further from the cylinder, a silencer in continuation of the said conduit, the saig silencer being situated at such a distance alon said pipe that the said gases substantially terminate their outward motion before entering salt} silencer. 9. The device as claimed in claim 4 in which the exhaust conduit comprises telescoping tubes, 2.

MICHEL KADENACY. Q 

